The American Podiatric Medical Association published a statistical document in 2001 relating that 18,035,600 U.S. residents over 18 were treated by physicians for heel pain in 2000, with another 20,619,200 self treated in the same year.
The present invention relates to a modified oxford shoe designed specifically for use by those experiencing chronic or acute foot pain. Precisely for therapeutic relief for those experiencing heel pain, sometimes disabling, which can occur in the back, sides and bottom of the heel with other symptoms of inflammation, redness, swelling and heat. Practitioners in the field recognize that pressures on the heel can cause pain to an otherwise uninjured heel, and that pressures on an injured heel tend to aggravate the inflammation while recovering thus extending the healing time.
Secondarily, the modified oxford shoe provides a means of correcting biomechanical imbalance such as excessive pronation which may cause chronic heel pain and may also contribute to injury to the knee, hip and lower back.
The primary purpose of shoes is to protect the foot from injury. The sole protects the bottom of the foot and the upper protects the body of the foot. Shoe designers, through their ingenuity and tenacity, have developed excellent concepts and designs for protective sports shoes. Some of these, the padded tongue, the padded collar and resilient midsole have trickled down to the walking shoe which virtually every man, woman, and child wear for work, school or leisurexe2x80x94because they are comfortable.
There are occasions, however, that the comfort of these shoes is not sufficient for those incurring heel pain through injuries, heel spurs, malformations or mild to severe obesity which prompts the subject invention.
The function of a conventional counter, capped by a collar, is to hold the foot into the body of the shoe and to cover the heel of the wearer. The counter of an oxford shoe, the basic design of a walking shoe, is a stiffened piece of leather, cotton or synthetic material around and attached to the heel of a shoe, formed upward and forward to follow the contour of the wearers heel creating a small encapsulated pocket which does not allow sufficient upward or downward movement of the rear of the wearers heel within the shoe to allow for a satisfactory range of internal cushioning because of friction leading to blisters. Therefore the widely sold resilient plastic heel inserts are thin and flimsy resulting in a minuscule level of cushioning, and when compressed present the same unyielding face as the underlying mass.
To attain more cushioning, it is not unusual for the buyers of the inserts to double up on these cushions in the hope of better cushioning. This lead to thicker more expensive resilient plastic inserts which have two disadvantages beyond the limited range of cushioning, especially when the wearer is experiencing severe heel pain. These inserts are flat across the beam and taper forward and downward to a point one half inch or so from the front, whereupon they abruptly taper to zero to meet the plane of the insole liner. When weight from the bottom of the heel compresses the insert, the heel forms a cup shaped depression in the top surface of the insert causing stretching of the surface resulting in a stiffening of the surface and resultant inward pressure to the heel by the sides of the depression, however slight. The weight placed by the heel upon the insert does not in any means fully compress the insert and in effect the insert then presents a non-resilient surface to the heel. The remaining height of the insert, regardless of the two tapers, raises the plane of the heel above the plane of the pad of the foot forward of the heel, therefore does not allow proper load sharing of the whole foot causing callousing to occur in the forward part of the foot with resulting additional discomfort to the foot.
Another problem that one with heel pain would encounter with a conventional fixed counter is the patients heel would in fact encounter the counter with any sideward motion of the foot creating pressure resulting in a higher degree of pain.
The corrective devices for adjusting pronation are hard plastic inserts supporting the foot from the heel through the ball. These devices are contoured as the foot should be, not as it is, resulting in substantial discomfort to the wearer. The inserts are supplied with directions acknowledging this fact and advising using these for an hour a day as a start of a progressive program to make the transition to everyday wear. Some of these devices are thicker custom designed, poorly padded and more expensive than those sold to the mass market with generic designs. The buyers of these devices generally try and discard them because of the continuing discomfort.
Utilizing steel springs as heel cushioning devices has been enduring art for many years. Early versions placed the springs in a heel under the sole of a shoe or boot which merely provided cushioning action for a healthy heel from the ground up to the sole of the shoe with hard barriers; sole, insole and leather heel liner as a platform for the wearer""s heel. These methods are disclosed in U.S. Pat. Nos.: 384,634 1888 Martin; 1,094,211 1914 Jenoi 1,099,180 1914 Karacsonyi; 1,098,241 1914 Forray; 1,338,817 1920 De Luca; 2,535,102 1950 Taylor; and 2,669,038 1954 De Werth. Later with the advent of sports shoes the focus turned to shock absorption, stability and energy return through spring related devices as shown in U.S. Pat. Nos.: 5,544,431 1966 Dixon; 5,649,374 1997 Chou; 5,651,196 1997 Hsieh; 5,729,916 1998 Vorobiev; 5,743,028 1998 Lombardino; 5,832,629, 1998 Wen; 6,006,449 1999 Orlowski; and 6,055,747 2000 Lombardino.
While the concepts and designs of these devices or shoes may be effective for their intended uses, they all contain cushioning obstructions, barriers and impedences which negate their performance when attempting to eliminate pressure, or reduce the sense of impression caused by compression to an injured heel.
Specifically, this representative group has disclosed no suitable, by design or implication, direct adjustable cushioning extending unimpededly from the patients heel to the floor for this purpose.
Properly designed and manufactured oxford shoes are available in various lengths and widths to provide a comfortable supportive fit. There is no provision for inserts which change the working dimensions of the shoe. This demands the most cautious discretion in making internal changes to a shoe unless other compensating adjustments are made to the shoe.
There are those practitioners who feel that the platform for the pad of a foot should not be flat as generally manufactured. Since the heel pad is lower in its static state than the adjoining foot pad, they reason that the platform of a shoe should have a depression in the heel to conform with this. The fact that this may be controversial and difficult to engineer appears to be the basis for the flat platform existing in most shoes.
The objects of the present invention are: To provide a shoe which immediately delivers vertical and horizontal heel pressure diminishment for those experiencing acute or chronic heel pain;
To provide a series of heel cushioning, with no intervening barriers or other impedences, extending from the patients heel to the floor;
To provide a vertical heel pad cushioning series independent of any lateral or lengthwise forces upon which the patients heel directly rests, and exerts downward pressure upon to receive buoyantly elastic cushioning;
To provide a cushioning element which spreads the downward pressure from the patients heel over a larger area of buoyantly elastic cushioning springs;
To provide a variety of calibrated compression springs of various cushioning resistance for selection by the patient determined by the patients weight and degree of buoyantly elastic cushioning desired;
To provide ease of access to the calibrated springs for periodic patient changing;
To provide a secondary cushioning series, wherein the first element of cushioning, compresses additionally to bridge the transition from buoyantly elastic to resiliently elastic cushioning when the calibrated springs are depressed to a limit determined by the depth of the resilient floor of the upper midsole cavity. On this occasion the bottom of the lower portion of the cushion assembly rests upon this resilient floor, and additionally spreads the downward pressure. Simultaneously, the elastic periphery of the upper and lower midsole cavities is compressed by the resilient flexible face of the wearing surface providing a cushioning effect against the lower faces of the calibrated springs. At no point are the springs fully compressed;
To provide the patient the ability to tilt the cushion assembly, if needed, to adjust the interface with the patients heel;
To provide a floating collar and supple upper counter assembly with adjusting strap whereby the upper counter is not attached to the heel of the shoe and the movement of the assembly is generally controlled by the padded collar preventing internal pressures to the heel or heel stem. The adjusting strap ends can be partially or fully released to allow a longer range of motion to accommodate sideward motion of the heels;
To provide strategically placed removable spacing studs for the midsole to eliminate exterior pressure to the patients heel while driving;
To provide a therapeutic shoe in attractive contemporary designs with several finishes for prolonged use.
Other objects and advantages of the present invention will become obvious to the reader and it is intended that these objects and advantages are within the scope of the present invention.
In this invention the vertical and horizontal heel pressure diminishment for those experiencing chronic or acute heel pain is achieved with a number of both internal and external modifications to a shoe of oxford design.
A floating collar and supple counter assembly with adjusting strap eliminates side and rear interior pressure to the patients heel by virtue of the collar assembly not being fixedly attached to the heel of the shoe. The collar assemblies pivot points at the upper waist of the shoe, the suppleness of the counter and the straps adjustment function allow the collar assemblies upward, downward, left and right movement to occur with no internal pressure to the heel.
A series of removable spacing studs mounted strategically onto the vertical sides of the shoes midsole which eliminate external pressure to the heel when the shoe is on edge while driving. At this stage the floating collar assembly will shift to the downside eliminating internal pressure from the patients heel to the counter. The floating collar assembly will then cradle the rear of the foot. The spacing studs will provide clearance between the counter and the floor of the vehicle which eliminates any external pressure to the heel.
A bidirectional unimpeded series of adjustable cushioning to the bottom of the heel, extending directly from the patients heel to the floor.
The elements of this cushioning series includes from the top 1) A laminated cushion assembly with the upper portion formed of resilient gel type plastic with an initial elliptical oblique terrace which conforms to the shape and direction of the patients heel, followed by other oblique terraces, and portions thereof, which sequentially increase in area until reaching the lower portion, which is formed of flexible plastic with twelve positioning studs, which rests upon 2) Twelve calibrated, changeable by patient, steel springs in three files which extend through 3) An upper midsole cavity in the resilient midsole sized to accommodate the cushion assembly under pressure from the patients heel. 4) Twelve lower midsole spring holding cavities, wherein the springs rest upon the wearing surface of the shoe attached to the midsole. 5) The exterior face of the wearing surface bordered by the chamfers fore and aft of the heel.
The following will further explain the mechanics of the direct unimpeded series of adjustable cushioning for the bottom of the heel.
For one with intense heel pain, the aggregate cushion value of the twelve calibrated springs per shoe should start at twenty five percent of the clothed body weight for the initial fitting.
The patient, with both shoes on, should stand upright with the feet comfortably apart, which spreads the body weight to the pads of both feet.
The conformation of the patients body then will determine the portion of full body weight directed to the heels. This can be determined by the patient rocking gently forward and backward. The patient should be able to feel the cushion assembly rise going forward and depress going backward.
At this point this is what has happened: with the patient standing, pressure from the patient""s heels depressed the top oblique cushioning terrace of the cushion assembly into the second oblique cushioning terrace with no cupping or stretching back pressure; the lower part of the cushion assembly spread and shared the downward pressure with the upper faces of the twelve calibrated springs beneath, which then compressed into the upper midsole cavity giving buoyantly elastic cushioning to the heel; the supple counters of the floating collar and supple counter assembly with adjusting strap flex downwardly under the downward motion, resulting in no irritating movement of the collar or counter against the heel or heel stems; additional indirect downward pressure from the foot structures, adjacently forward of the cushion assembly, is exerted through the midsole to the flexible resilient outer faces of the shoes wearing surfaces, causing pressure which slightly compresses the lower faces of the twelve calibrated springs and the lower face of the lower midsole cavities providing a measure of additional cushioning. All of this occurs in milliseconds.
As the patient rocks forward: The collars of the floating collar and counter assemblies with adjusting straps, under slight upward pressure from the heel stem rise causing the supple counters, along with the adjusting straps, to unflex and rise slightly from the midsole; this places no pressure on the heel or heel stem; the downward pressure from the heels ceases, allowing both the elliptical terraces and the springs to regain their static condition, as do the flexible faces of the wearing surfaces.
When the patient rocks backward the above standing sequences repeat. Then the extra pressure from more weight exerted upon the heels causes: The calibrated springs to compress further allowing the lower portion of the cushion assembly to rest upon the floor of the upper midsole cavity; the patients heels further compress the oblique cushioning terraces; pressure is exerted upon the floor of the resilient upper midsole by the cushion assembly; pressure is exerted upon the flexible resilient outer face of the shoes heel wearing surface causing sandwich pressure upon the floor of the upper midsole cavity and the bottom plane of the lower midsole spring cavities along with both ends of the calibrated springs which produces resilient elastic cushioning.
The action of standing, rocking forward and rocking rearward, as described, demonstrates the dynamics of the elements of the bidirectional unimpeded series of adjustable cushioning.
The cushion assembly under downward pressure from the patients heel hovers within the upper midsole cavity over its floor, as described. In this position, the heel is on plane with the rest of the foot pad which eliminates the prevailing problem of improper weight loading to the forward pads of the foot by conventional heel inserts.
In this hovering state only a portion of the oblique elliptical terraces are compressed thus retaining resiliency while sharing the load with the resilient springs beneath. There is no cupping or full compression of the oblique elliptical terraces occurring in the area contacted by the patients heel.
When a step is taken and the lead heel contacts the floor at the point of the rear midsole chamfer, pressure is exerted simultaneously upon the lower face of the wearing surface and the cushion assembly initiating cushioning. As the face of the heel wearing surface becomes horizontal, the primary force is downward from the patients heel to the top oblique ellipse. With some terraces compressing the load is spread from the patient""s heel area over the larger area of the cushion assembly reducing effective pressure to the patients heel as the load is shared with the twelve springs. The springs may compress on plane with the floor of the upper midsole cavity, at which time the remaining terraces of the cushion assembly resiliently compress instantly sharing the load with the floor of the upper midsole cavity. As the foot rolls forward the pressure to the patients heel is reduced to zero.
This sequence does not occur with conventional heel inserts nor any of the prior art relating to spring cushioning of the heel.
The springs are the only variable element of the bidirectional unimpeded series of adjustable cushioning found in this invention. The initial strength of the springs is determined by a percentage of the clothed weight of the patient and then adjusted by the patient, who best knows, for the patients level of comfort. For this reason the springs are readily accessible for changing by lifting the cushion assembly.
The skeletal integrity of the human body relies substantially upon the stability of its platform, the feet. Practioners in the field have relied on inserts to correct insufficiencies in this area. These, as described, are contoured as the foot should be, which is too much treatment too fast in addition to defeating proper sizing of a shoe.
The platform presented to a patients heel in the present invention rests on and is controlled by the underlying springs. The positions of the springs and the clearances provided by the cushion assembly lends itself to tilting with springs of varying strengths properly placed to provide a sequential training force to receive correction without discomfort.